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LESSON PLAN: NEWTON’S LAWS OF MOTION DAY 1
Candidate: Brian Turkett
Date:Friday, November 20, 2009
Cooperating Teacher:Michael Occhino
Grade Level: 9
Subject Area:Physical Science
Duration:80 hours
Title of Unit:Newton’s Laws of Motion
Lesson Title:Inertia, Mass, and Force 1
Goals and Objectives
Goals:
· Students will understand that inertia is an object’s resistance to being accelerated, which is characterized by an objects mass.
· Students will understand that an object only changes its motion when a net force is applied.
· Students will understand that a state of equilibrium is when the net force is equal to zero.
· Students will formulate that force is proportional to acceleration.
Objectives:
· Students will predict, observe, and explain results of demonstrations relating to inertial processes and construct connections to acceleration using dynamic carts, weights, and pulleys.
· Students will identify specific forces acting on an object and their impact on the entire system by drawing free-body diagrams and building models using weights, pulleys, and dynamic carts.
· Students will learn how to solve force and motion problems through homework exercises and challenges.
· Students will draw and use accurate free-body diagrams for classroom demonstrations and a force lab using dynamic carts and pulleys.
· Students will understand the connection between force and motion by using weights, a pulley, dynamic carts, and force, acceleration, and motion probes to manipulate and measure a dynamic system.
National and New York State Standards:
New York State Standard: Physics
5.1 Explain and predict different patterns of motion of objects (e.g., linear and uniform circular motion, velocity and acceleration, momentum and inertia).
i. construct and interpret graphs of position, velocity, or acceleration versus time
ii. determine and interpret slopes and areas of motion graphs
viii. use vector diagrams to analyze mechanical systems (equilibrium and nonequilibrium)
ix. verify Newton’s Second Law for linear motion
Performance Indicator 5.1
5.1i According to Newton’s First Law, the inertia of an object is directly proportional to its mass. An object remains at rest or moves with constant velocity, unless acted upon by an unbalanced force.
5.1j When the net force on a system is zero, the system is in equilibrium.
5.1k According to Newton’s Second Law, an unbalanced force causes a mass to accelerate.
5.1p The impulse imparted to an object causes a change in its momentum.
5.1q According to Newton’s Third Law, forces occur in action/reaction pairs. When one object exerts a force on a second, the second exerts a force on the first that is equal in magnitude and opposite in direction.
Assessment:
Formative:
The formative assessments are spread out across the lesson. Students will create a definition of force through discussion as a class at the beginning of the lesson that they will revisit again at the end of the lesson. Students will explore inertia systems through hands-on activities that assess students understanding of a system where a heavier mass is on top of a less massive object they will be required to move with the restriction that they cannot move the heavier objects. Student knowledge will be assessed by their recording on the POE for the tablecloth, the washer, and the hoop activities. These will be used to assess conceptual change in the overall POE of Newton’s 1st law being conducted through the egg drop. Students will draw free-body diagrams to represent their understanding of the forces inherent to a system both in demonstrations and lab. Students will also begin using the equation F=ma to investigate graphs produced using motion detectors on the dynamic carts through calculating force with experimental mass and acceleration data.
Summative:
There are two summative assessments in this lesson. First, the students will complete a POE worksheet for the inertial egg drop demonstration, enriched by their own experiences with the coin tumbler, the hoop, and the tablecloth demonstrations. This assessment will display students’ prior conceptions behind the system and their final interpretations of how the mass of an object effects its acceleration and the forces external and internal to it within the systems. The second assessment is an ongoing one across the entire unit of three lessons, beginning today. This assessment is the lab the students will be investigating using dynamic carts, weights, and pulleys. From this lab students should learn about the net force of a system, and how Newton’s 1st law is a special case of Newton’s 2nd law, as well as that force is proportional to acceleration by using their data and analysis to support Newton’s three laws of motion. A final assessment will be an examination that tests student knowledge and understanding of Newton’s laws of motion and kinematic motion.
Community Knowledge and Experience:
Students will be using their prior knowledge of motion in every activity. As a community, they will all share in exploring physical demonstrations and manipulating dynamic systems in order to understand inertial principles and the influence of forces on objects in or not in motion. Students will be able to share their previous experiences and these experiences with the demonstrations in dealing with forces with each other, in order to build a larger field of evidence for the support of Newton’s Laws of Motion.
Procedures/Format: *All activity accompanied by Powerpoint slides
Time (~80 mins) / Materials / Activity / Description / Alternatives0 – 10 min
10 mins / White Board
Powerpoint / Force Introduction / Define Force. What is a force? Are forces always animate? Four fundamental forces (EM, strong, weak, gravity). What happens if there is no force on an object?
10 – 40 min
30 min / POE worksheet
Egg drop –
eggs
beakers
water
pie plates
toilet paper rolls
broom
desk
Coin tumbler –
Washers
Index cards
Flasks
The hoop –
Embroidery hoop
Nails
Flask
Tablecloth –
Tablecloth
Dishwear
Table / Introducing Newton’s 1st law:
Inertia Demonstrations / Students will be given a POE. The main demonstration is the egg drop. I will stand in the front of the classroom with the demonstration and the students will observe from group tables around the classroom. Students will view the set-up and be asked to make a prediction of what will happen to each object when I release the broom. We will then proceed to allow students to test inertia demonstrations: The coin tumbler, the hoop, and the tablecloth. After these observations and experimentation the students will make new predictions of what they think will happen. I will then display the results. If there is time we can kick it up a notch by setting up four beakers with four eggs and see how that works, or a higher paper roll.
What does this tell us about the forces surrounding these systems? Mass and acceleration. / It may not be possible to have the students do all the activities at once. The coin tumbler is the main focus for this activity followed by the hoop and tablecloth demos.
40 – 50 min
10 min / White Board
Powerpoint / Introducing Newton’s 2nd law / Students will learn the equation F=ma and the units associated with those parts. They will learn the units for each variable and the relationship the equation suggests between mass, force, and acceleration. This will be done through questioning, such as “how does this relate mass to acceleration? Force to acceleration?”
50 – 75 min
25 min / Dynamics carts
Weights
Pulleys
Lab notebook
Lab worksheet
Motion detectors / Newton Lab / Students will be using dynamic carts, weights, and pulleys to make systems that represent Newton’s three laws of motion. Students will be exploring keeping forces constant and changing masses, keeping masses constant and changing forces, and the impact of multiple bodies. This lab focuses on the goals of this unit, offering many dynamic systems for the students to explore and manipulate and construct their knowledge and understanding of Newton’s laws of motion. / Students will be dismissed to lab tables once they have formed groups and seen me.
75-78 min
3 min / Clean-up
78 – 80
2 min / Review of the day’s lesson – Key points / What is a force?
How does an objects mass affect force? Acceleration? This will be done through class discussion.
Safety:
Students will need to take care of materials when conducting inertial demonstrations. Review of glass disposal and cautionary safety procedures will be reviewed by powerpoint and discussion. In working with dynamic carts, pulleys, and weights students need to be careful in how they setup their systems. Any inappropriate use of materials, including letting the dynamic carts fall off the table, not securing weights, or breaking any instruments, will result in that student having to sit in their seats away from the equipment for the rest of the day.
Resources:
POE worksheet
Egg drop –
eggs
beakers
water
pie plates
toilet paper rolls
broom
desk
Coin tumbler –
Washers
Index cards
Flasks The hoop –
Embroidery hoop
Nails
Flask
Tablecloth –
Tablecloth
Dishwear
Table
White Board
Powerpoint
Dynamics carts
Weights
Pulleys
Lab notebook
Lab worksheet
Motion Detectors
Applications, Connections and Extensions:
There will be many applications, connections, and extensions to real-life experiences. Inertia references can be made to riding on a train, riding in a car, and pushing a heavy object compared to a lighter object. These tie into other physics concepts of circular motion and acceleration. Application of forces will be found in many everyday experiences as well, such as throwing a baseball or skiing down a hill. Hidden forces will also be discovered, such as gravity, friction, normal force, etc and will influence a greater understanding of dynamic systems. Students will be able to tie these experiences to their previous work on motion that includes velocity and acceleration. Previously they have manipulated their motions using a motion detector to explore velocities and accelerations, and they can use this experience as comparisons and support in their observations and explorations of the dynamic and static systems we will be investigating.
Inclusive Instruction:
The lab on Newton’s laws of motion will require many roles that can be developed and assigned to specific students needs and strengths as instruction necessitates. The inertia demonstrations can also be expanded to include participation of students in physical experiences and hands-on observation or manipulation. Specifically, students that do not have a lot of opportunities to be involved in discussion or students that are struggling in understanding should be allowed to carry out these demonstrations. Students that are of consideration include Robert, Destiny, and Ashley in the first class and Troy, Alexis, and Kendra in the second class. All students will get the opportunity to participate in a group during the washer activity to try and solve the problem of moving the index card out from under the washer without moving the washer.
Reflection
I learned a lot from this lesson. To begin with, this was the day that I was being observed by my supervisor Jim Davidson. Under the RTOP sections I wanted to focus on conceptual knowledge. My plan was to introduce the idea of forces through building a definition and discussing some important ideas around forces such as forces are not always observable and that forces do not always need to cause objects to move or be animate. The purpose of this to me was to give students an idea of how many forces we know about in nature, which isn’t many, and that how we may think a system or object operates may be completely different than how it actually does because of unseen forces. Jim had mentioned that this part of the lesson was disjointed and the connection of this to everything else that we were doing would have been good. In particular, I asked the students “Are all forces animate?” I’m not sure if the students understood this question or got anything out of it. In the future I want to try to not only try to show the purpose behind all my questions but also to find ways to assess whether the questions are effective. I think there was confusion found in whether I was addressing if forces were always animate or whether objects that were experiencing forces were always animate. To clarify this I should challenge students with a question relating these two ideas and see how they answer.
The POE worked well. Students expressed in their predictions, observations, and explanations over time the concepts of mass and resisting motion (inertia). I think something I could add to these demonstrations is a talk about force body diagrams. It would have been a great time to discuss them and could change the students thinking about the static systems and their predictions regarding what might happen. In general, an arrow I have is to write more and explain through visual. I spoke a lot, which is great for the auditory learners, but I need to help those visual learners feel more comfortable. Showing examples of the force diagrams and equations with numbers would help this lesson out greatly. The POE was connected very well I thought, with students knowledge being scaffolded through each experience up to the final demonstration of the egg falling into the beaker. The big arrow to place here is my transition into talking about Newton’s laws of motion. I never connected these POE’s to Newton’s first law of motion directly. Taking some time to focus on the inertial aspect as well as the mass of the bodies and why the object’s didn’t accelerate forward with a force is important to highlight, and how this supports Newton’s first law. The students loved the demonstrations and were actively involved and participating in exploring them. To enhance this I should allow more opportunity for them to do the demonstrations. Asking for volunteers was something that worked well during this, but offering the opportunity to a lot more students would be better. I also would like to focus on the social justice aspect of this participation a lot more next time, including students who may not have these opportunities a lot more.
The last two parts of the lesson need work. I provided the students with all three Newton’s laws of motion at once. Instead, I think it would have been good to do one activity at a time that focuses on one of the laws and then bringing them back up for reflection on their observations and results. Then we can discuss what they think a law for these results could be and provide them with Newton’s law for that particular activity and they can then support or refute Newton’s law using their evidence. A discussion of who exactly Isaac Newton was and why he is so important would have been a great historical component to add to the lesson as well. Also, I was talking about the laws as they were writing them down, asking them what the laws mean. When they are taking notes I should let them write and think about it for a bit before prompting them with a question. There was a lot of writing as well, so maybe I could have a printout that has these laws and history written down to save time and enhance a deeper discussion quicker.